Core D will provide microbial community compositional profiling for Projects 1, 2, 3 and 4 with next- generation biomarker sequencing. Having a centralized processing core for sequencing will reduce variation due to sample processing during gDNA extraction, PCR amplification, sequencing steps and data normalization. Core D is highly qualified to perform such assays as is exemplified by the data generated and published in our previous collaborative projects and preliminary data. These studies have allowed us to demonstrate that vertical transfer of maternal microbiome to her infant occurs and that pioneer communities associate with distinct microbiome developmental trajectories in high-risk-for-asthma infants compared to low- risk controls. Core D has the personnel expertise, equipment and capacity to provide timely high-throughput microbial sequencing to all four projects in this application.